From: Gary Wright <gwtmp01@...>
Date: 2007-11-06T04:35:28+09:00
Subject: Re: x=[]; x[:bla][:some_key] does not work?


On Nov 5, 2007, at 5:27 AM, David A. Black wrote:
> My favorite is:
>
>   class NonexistentKeyError < StandardError
>   end
>
>   hash = Hash.new {|h,k| raise NonexistentKeyError, "No such key: # 
> {k}" }

An alternate solution:

    a = Hash.new { |h,k| h.fetch k }

David's solution is nice because the message includes
the key.  Maybe Ruby's IndexError message should
report the unknown key.

Gary Wright